In vitro effects of methotrexate on peripheral blood monocytes: modulation by folinic acid and S-adenosylmethionine.

The mechanism of action of low dose methotrexate in rheumatoid arthritis has not been established. It has been shown to have an anti-inflammatory effect and to inhibit neutrophil chemotaxis, but the effect on monocytes has not been widely studied. Normal donor peripheral blood monocytes were incubated with methotrexate in vitro and their superoxide production, chemotaxis, and phagocytosis subsequently assessed. Additionally, the influence of different culture media, and of folinic acid, and the methyl donor S-adenosylmethionine, and spermidine on the methotrexate mediated effects were evaluated. It was found that methotrexate in low concentrations inhibited in vitro monocyte chemotaxis and superoxide production but only after prolonged incubation. This inhibition was augmented by incubation in medium containing a low methionine concentration and was abolished by folinic acid and S-adenosylmethionine, suggesting that methotrexate may interfere with specific methylation reactions.     

Epitrochlearis muscle. I. Mechanical performance, energetics, and fiber composition

An in vitro rat muscle preparation is described that can contract at rates of 12-240 twitches/min. Maximum dF/dt paralleled maximum twitch tension, their ratio being constant at approximately 8 ms for contraction rates of 12-120 twitches/min. Time to peak tension was 8-13 ms, time to peak dF/dt 5-8 ms, and half-relaxation time 4 ms. These parameters were unaffected by rate of contraction or duration of isometric work. Differential ATPase staining demonstrated that 60-65% of the fibers were fast-twitch white, 20% fast-twitch red, and 15% slow-twitch red. The preponderance of fast-twitch fibers correlated with the observed mechanical performance of the muscle. Muscles contracting for 60 min at rates up to 48 twitches/min maintained total adenine nucleotide content (ATP, ADP, AMP) at near resting levels. At higher twitch rates (72-240 twitches/min), total adenine nucleotide content decreased 40%, reflecting exclusively a fall in ATP in the presence of adequate phosphocreatine stores. Adequate oxygenation was reflected by lactate-to-pyruvate ratios in the range of 11-15 at all rates of contraction.     

Trends in the clinical presentation of temporal arteritis in israel: Reflection of increased physician awareness

Summary We have noticed significant changes in the clinical presentation in patients diagnosed with temporal arteritis in Israel between 1980–1992 compared to patients diagnosed prior to 1977. At the time of diagnosis 57% of the patients were older than 75 years, compared to only 23% within this age group in the previous period. There was an increase in the number of nonspecific and unusual presenting symptoms such as weakness, respiratory and neurological symptomatology, and a decreased proportion of patients presenting with the classical manifestation such as headaches, temporal tenderness and visual symptoms. The time from presentation to diagnosis was shortened significantly. It is suggested that these changes are largely due to the increasing awareness among physicians to the various manifestations of this conditions.     

Molteno implants in children

We report our experience with Molteno implants in 27 eyes of 20 children with glaucoma. Associated ocular findings included Sturge Weber syndrome (one patient), aniridia and retinoschisis (one patient), aphakia (seven patients, eight eyes), rubella syndrome (two patients), Peters anomaly (one patient), and Treacher Collins syndrome (one patient). Fifteen eyes received a single-plate implant, and 12 eyes received a double-plate implant in two stages. The patients' ages ranged from 2 months to 13 years (mean 47 +/- 55 months). The average number of previous glaucoma procedures was four per eye (range two to 10). The follow-up period ranged from 6 to 36 months (mean 20 +/- 9 months). The mean intraocular pressure before surgery was 34 +/- 4 mm Hg. The mean postoperative intraocular pressure was 19 +/- 11 mm Hg at 1 month and 19 +/- 6 mm Hg at 1 year (p < 0.001 at both times). After surgery nine eyes (33.3%) required no medication for control of intraocular pressure. Additional surgery was required in 12 eyes (44.4%). We believe the Molteno implant is a useful approach for children with glaucoma who fail to respond to standard medical and surgical treatments.     

In vivo fragmentation of heparan sulfate by heparanase overexpression renders mice resistant to amyloid protein A amyloidosis

Amyloid diseases encompass >20 medical disorders that include amyloid protein A (AA) amyloidosis, Alzheimer's disease, and type 2 diabetes. A common feature of these conditions is the selective organ deposition of disease-specific fibrillar proteins, along with the sulfated glycosaminoglycan, heparan sulfate. We have generated transgenic mice that overexpress human heparanase and have tested their susceptibility to amyloid induction. Drastic shortening of heparan sulfate chains was observed in heparanase-overproducing organs, such as liver and kidney. These sites selectively escaped amyloid deposition on experimental induction of inflammation-associated AA amyloidosis, as verified by lack of material staining with Congo Red, as well as lack of associated polysaccharide, whereas the same tissues from control animals were heavily infiltrated with amyloid. By contrast, the spleens of transgenic mice that failed to significantly overexpress heparanase contained heparan sulfate chains similar in size to those of control spleen and remained susceptible to amyloid deposition. Our findings provide direct in vivo evidence that heparan sulfate is essential for the development of amyloid disease.     

Perceived efficacy among patients of various methods of complementary alternative medicine for rheumatologic diseases

OBJECTIVE: The purpose of this cross-sectional survey was to obtain and analyze data on self-perceived efficacy of different types of complementary alternative medicine (CAM) by patients with various rheumatologic conditions. METHODS: Patients followed in rheumatology outpatient clinics were screened for the use of CAM. Patients reporting the use of CAM were asked to participate in face-to-face structured interviews, specifying the various CAM types they used, and grading their subjective impression of efficacy of each CAM type on a scale of 1-10. RESULTS: 350 consecutive patients were screened and 148 reported using CAM. In general, homeopathy and acupuncture were the most commonly used CAM types (44% and 41% of the CAM users, respectively). The mean number of different CAM methods used by a CAM user was 1.9 +/- 1.1. Patients with fibromyalgia used significantly more CAM methods (2.7 +/- 1.4, p = 0.005). On patients' self-perceived efficacy scale of 1-10, the mean score of the whole group was 5.3 +/- 3.2. Acupuncture and homeopathy achieved significantly higher self-perceived efficacy scores in CAM users with spondylo-arthropathies and osteoarthritis, respectively, when compared to some of the other disease groups. Satisfaction was lowest among CAM users with rheumatoid arthritis, vasculitis and connective tissue diseases. CONCLUSION: In general, CAM users were less than moderately satisfied with self-perceived-efficacy of CAM therapies. However efficacy of specific CAM methods differed significantly among patients in different disease groups.     

Nanostructural control of the release of macromolecules from silica sol–gels

The therapeutic use of biological molecules such as growth factors and monoclonal antibodies is challenging in view of their limited half-life in vivo. This has elicited the interest in delivery materials that can protect these molecules until released over extended periods of time. Although previous studies have shown controlled release of biologically functional BMP-2 and TGF-β from silica sol–gels, more versatile release conditions are desirable. This study focuses on the relationship between room temperature processed silica sol–gel synthesis conditions and the nanopore size and size distribution of the sol–gels. Furthermore, the effect on release of large molecules with a size up to 70 kDa is determined. Dextran, a hydrophilic polysaccharide, was selected as a large model molecule at molecular sizes of 10, 40 and 70 kDa, as it enabled us to determine a size effect uniquely without possible confounding chemical effects arising from the various molecules used. Previously, acid catalysis was performed at a pH value of 1.8 below the isoelectric point of silica. Herein the silica synthesis was pursued using acid catalysis at either pH 1.8 or 3.05 first, followed by catalysis at higher values by adding base. This results in a mesoporous structure with an abundance of pores around 3.5 nm. The data show that all molecular sizes can be released in a controlled manner. The data also reveal a unique in vivo approach to enable release of large biological molecules: the use more labile sol–gel structures by acid catalyzing above the pH value of the isoelectric point of silica; upon immersion in a physiological fluid the pores expand to reach an average size of 3.5 nm, thereby facilitating molecular out-diffusion.     

Nonverbal imitation skills in children with specific language delay

Research in children with language problems has focussed on verbal deficits, and we have less understanding of children's deficits with nonverbal sociocognitive skills which have been proposed to be important for language acquisition. This study was designed to investigate elicited nonverbal imitation in children with specific language delay (SLD). It is argued that difficulties in nonverbal imitation, which do not involve the processing of structural aspects of language, may be indicative of sociocognitive deficits. Participants were German-speaking typically developing children (n = 60) and children with SLD (n = 45) aged 2–3½ years. A novel battery of tasks measured their ability to imitate a range of nonverbal target acts that to a greater or lesser extent involve sociocognitive skills (body movements, instrumental acts on objects, pretend acts). Significant group differences were found for all body movement and pretend act tasks, but not for the instrumental act tasks. The poorer imitative performance of the SLD sample was not explained by motor or nonverbal cognitive skills. Thus, it appeared that the nature of the task affected children's imitation performance. It is argued that the ability to establish a sense of connectedness with the demonstrator was at the core of children's imitation difficulty in the SLD sample.     

Flow-controlled fluoroscopic angiography for the assessment of vascular integrity in bioengineered kidneys

Perfusion decellularization has been proposed as a promising method for generating nonimmunogenic organs from allogeneic or xenogeneic donors. Several imaging modalities have been used to assess vascular integrity in bioengineered organs with no consistency in the methodology used. Here, we studied the use of fluoroscopic angiography performed under controlled flow conditions for vascular integrity assessment in bioengineered kidneys. Porcine kidneys underwent ex vivo angiography before and after perfusion decellularization. Arterial and venous patencies were defined as visualization of contrast medium (CM) in distal capillaries and renal vein, respectively. Changes in vascular permeability were visualized and quantified. No differences in patency were detected in decellularized kidneys compared with native kidneys. However, focal parenchymal opacities and significant delay in CM clearance were detected in decellularized kidneys, indicating increased permeability. Biopsy-induced leakage was visualized in both groups, with digital subtraction angiography revealing minimal CM leakage earlier than nonsubtracted fluoroscopy. In summary, quantitative assessment of vascular permeability should be coupled with patency when studying the effect of perfusion decellularization on kidney vasculature. Flow-controlled angiography should be considered as the method of choice for vascular assessment in bioengineered kidneys. Adopting this methodology for organs premodified ex vivo under normothermic machine perfusion settings is also suggested.